1 definition by Ian Relihan

1. One who is characterized by foolishness or a lack of common sense.

2. a)One who habitually ruins jokes by attempting to build upon them with tired puns and witticisms.

b) A person who often makes remarks intended to be humorous, but fails to do so by fumbling the delievery.
After Tom made a bad joke, we stopped him from telling another one by calling him a Jacob.
by Ian Relihan June 11, 2005
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